Mobile excavator

ABSTRACT

An excavator vehicle with a crane mounted near one end rotatably about a vertical axis. The vehicle has at or near the said end two support legs with adjustable length, adapted to be pivoted at their end connected to the vehicle about a horizontal and a vertical axis and to be fixed in both directions at different angular positions relative to the vehicle. The two support legs have at their free end an at least substantially horizontal support or a wheel adapted to be rotated about a horizontal axis. The vehicle has, at its other end, a third support leg which is also pivotable at its end mounted on the vehicle about a vertical and a horizontal axis and may be fixed in both directions in different angular positions relative to the vehicle. The third support leg has at its free end a vertical plate or at least one wheel rotatable about a horizontal axis.

United States Patent [191 Konijn MOBILE EXCAVATOR [75] Inventor: Nicolaas Gerardus Konijn,

Berkhout, Netherlands [73] Assignee: KonijnMachinebouw,Hoorn, Netherlands 221 Filed: Apr. 13, 1972 21 Appl. No.: 243,699

[30] Foreign Application Priority Data Apr. 15, 1971 Netherlands 7105085 [56] References Cited UNITED STATES PATENTS 3,479,049 ll/l969 Duecy 280/43.23 X FOREIGN PATENTS 0R APPLICATIONS 767,420 Great Britain 280/34 R Dec. 11, 1973 Primary Examiner--Gerald M. Forlenza Assistant Examiner-George F. Abraham Att0rneyEric H. Waters et al.

[57] ABSTRACT An excavator vehicle with a crane mounted near one end rotatably about a vertical axis. The vehicle has at or near the said end two support legs with adjustable length, adapted to be pivoted at their end connected to the vehicle about a horizontal and a vertical axis and to be fixed in both directions at different angular positions relative to the vehicle. The two support legs have at their free end an at least substantially horizontal support or a wheel adapted to be rotated about a horizontal axis. The vehicle has, at its other end, a third support leg which is also pivotable at its end mounted on the vehicle about a vertical and a horizontal axis and may be fixed in both directions in different angular positions relative to the vehicle. The third support leg has at its free end a vertical plate or at least one wheel rotatable about a horizontal axis.

15 Claims, 8 Drawing Figures PATENTED UEBI I I973 SHEET 2 BF 3 MOBILE EXCAVATOR BACKGROUND OF THE INVENTION The invention relates to a mobile excavator with a crane with grab mounted near one end of the excavator and rotatable about a vertical axis.

Hitherto known mobile excavators of this kind have a minimum width of about 2.5 m, so that they can be used in practice only in fairly wide ditches or channels.

To enable the crane to be slewed without the vehicle overturning, the vehicle has to be connected rigidly with a cross beam, resting with its two outer ends on the two banks. However, if the banks are of unequal height and irregular, this leads to time wasting adjustments which have to be made by hand because in this case the cross beam must be supported obliquely on the vehicle and the obliqueness must be altered during the movement of the vehicle.

By way of alternative for such a cross beam, a pontoon may be mounted detachably on either side of known mobile excavators, in order to improve the stability, but in this case the excavator can operate only in still wider ditches or channels.

In addition, the transfer of such mobile excavators from one ditch or channel into another ditch or channel not directly connected therewith requires much time because the mobile excavator must first be lifted out of the water and then be refloated after having been transported to the other ditch or channel.

SUMMARY OF THE INVENTION The present invention has the object of providing a mobile excavator of the type hereinbefore described, and constructed in such a way that the above mentioned difficulties may be reliably avoided.

To this end, a mobile excavator according to the invention is substantially characterized in that the vehicle has at or near the said end two support legs with adjustable length which are pivotable at their end connected to the vehicle about a vertical and a horizontal axis, and may be fixed in both pivoting senses in different angular positions relative to the vehicle and have at their free end an at least substantially horizontal support or a wheel rotatable about a horizontal axis, and in that the vehicle has at the other end a third support leg with adjustable length which is also pivotable at its end connected to the vehicle about a vertical and about a horizontal axis, and may be fixed in both directions in different angular positions relative to the vehicle, and has at its free end a vertical plate member or at least one wheel rotatable about a horizontal axis.

In veiw of this construction according to the invention, a mobile excavator with the supports mounted on the first two support legs mentioned above, may support itself on these supports on both banks or on the bottom of the ditch or channel. The latter possibility is used particularly for wider ditches or channels, and a pontoon may be mounted detachably on either side of the excavator to increase the stability.

During excavating work, the vertical plate member is mounted on the third support leg, causing it to cut into the bottom of the ditch or channel and to secure the associated end of the vehicle particularly against lateral movements.

In addition, the mobile excavator according to the invention may also be moved directly on dry land; for

this purpose the support legs may be equipped with wheels rotatable about horizontal axes.

This even enables the excavator according to the invention to move out of the water over the sloping bank, and vice versa to move back into the water from the bank, without having to use any special tools for this purpose.

The mobile excavator according to the invention may be constructed to have a narrow width of about 1.5 m or less. In consequence the mobile excavator according to the invention may operate in substantially narrower channels and ditches than hitherto known mobile excavators.

Preferably, the two first mentioned support legs are mounted on the front side of the vehicle near its two edges. The end of the third support leg connected with the vehicle is generally located in the longitudinal centre plane of the vehicle To enable a simple longitudinal adjustment of the support legs, these may be telescopic.

A particularly preferred embodiment of the excavator comprises that the first two support legs carry each at its free end a wheel rotatable about a horizontal axis and adapted to be positioned into the horizontal for use as support.

The invention also comprises a connecting structure whereby a pontoon may be mounted on the mobile excavator in a particularly rigid manner. This connecting structure is important independently and may be used also for detachably mounting a pontoon on a vehicle of a different kind, or for connecting sections of vehicles which are closed on the connection side by watertight bulkheads.

The connecting structure according to the invention is characterized substantially in that one of the elements to be connected has near its base at the side facing the other element a number of compartments extending obliquely downwardly and inwardly, having an inlet orifice at the outer edge, while the other element has near the bottom on the side facing the first element an identical number of holders extending obliquely downwardly and outwardly, having in the horizontal direction the same spacing from each other as the compartments and adapted to fit into these compartments, whilst one of these elements has, on the said side near the upper edge, a number of horizontally projecting eyes or lugs adapted to fit into externally open receptacles formed near the upper edge of said side of the other element, and adapted to be fixed therein by means of a bar adapted to be pushed through holes in the upper wall and the lower wall of the corresponding receptacle and through the hole in the eye.

The conpartments and the holders may form an angle of about 30 with the vertical. The holders and the eyes may be mounted on the same element and may be vertically one above the other in pairs. Preferably, there are two compartments, and two holders as well as two eyes and two receptacles, provided near the vertical side edges of the corresponding sides of the elements to be interconnected.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in greater detail in the following description of a preferred embodiment shown in the accompanying drawings in which:

FIG. 1 shows the mobile excavator according to the invention during the execution of excavating work in side elevation;

FIG. 2 is a plan view of the excavator of FIG. 1 in which the crane and its grab have been omitted;

FIG. 3 is a side elevation of the mobile excavator according to'the invention shown in FIGS. 1 and 2 during movement over land;

FIG. 4 is a plan view of the excacator of FIG. 3 omitting crane and the grab;

FIG. 5 is a diagrammatical cross-section of the excavator showing the detachable connection of the pontoons;

FIGS. 6, 7 and 8 are details of the arrangements of FIG. 5 on an enlarged scale.

DESCRIPTION OF A PREFERRED EMBODIMENT The embodiment of a mobile excavator according to the invention shown in the drawing may have a length of 5 m and a width of 1.50 m to 1.00 m. The width of the excavator 1 with fitted pontoons 2 is increased by these pontoons by, e.g., 1.10 m. The draught of the vehicle 1 without pontoons 2 is about 0.50 m.

' The mobile excavator 1 comprises a watertight steel box with a deck 3 having two hatches 4 and 5. The cab is indicated at 6. In the forward part of the vehicle 1 there is a crane or jib 7 carrying a grab 8 and fixed to the bottom of the vehicle 1.

This crane or jib 7 with grab 8 has a generally known construction and is hydraulically operated. It may be slewed hydraulically through 360 and may also be hydraulically bent, and stretched or lifted by means of two hydraulic cyclinder-piston units 9, whilst the grab 8 may be opened and closed by a hydraulic cylinderpiston unit 10.

The vehicle 1 carries on its front edge two support legs 11 with adjustable length, and adapted to be swivelled with their end mounted on the vehicle about a vertical and a horizontal axis. The two support legs 11 may be fixed in both swivelling directions in different angular positions relative to the vehicle 1. At their free ends, the two support legs 11 have each a wheel 12 rotatable about a horizontal axis and equipped with a pneumatic tyre, which wheel can also be positioned into the horizontal and serves then as a supporting element. In this horizontal position the wheel 12 is secured against rotation.

The rear side of the vehicle 1 carries a third support leg 13 with adjustable length which is also pivotable about a vertical and a horizontal axis at its end mounted on the vehicle 1. Also this rear support leg 13 1 may be fixed in different angular positions relative to the vehicle 1 in both swivelling directions.

At its free end this rear support leg 13 carries a vertical plate member 14, or a horizontal axis 15 carrying two rotatably mounted wheels 16 with pneumatic tyres.

The two forward support legs 11 are mounted near the edges of the front side of the vehicle 1, whilst the end of the rear support leg 13, connected with the vehicle l, is located in the centre plane of the vehicle 1.

The support legs 11 and 13 are telescopic and consist each of two parts 11, 11" and 13', 13'', respectively. The outer parts 11" of the two forward support legs 11 mounted at its free end pivotably on the wheel 12, may be fixed in two different angular positions, offset relative to each other through 90 relative to the inner parts 11 of thelegs 11. To this end, one of the parts 11 or 11" of the legs 11 has two rows of holes arranged in spaced apart relationship in the longitudinal direction (not shown in the drawing), wherein the holes of one row are in a plane of the leg part 11' or 11" which is perpendicular to the plane passing through the holes of the other row. A fixing stud which is pushed through a hole in the other part 11" or 11 of the leg may, therefore, engage at different points of the part 11' or 11" of the leg 1 1 and at two angular positions of the leg part 11", offset relative to each other through so that, on the one hand, the length of the support .leg 11 can be varied, and on the other hand the part 11" of the leg 11 may be brought into the position necessary for the horizontal support of the wheel 12 and into the position in which the wheel 12 is rotatable about a horizontal axis.

Since the outer part 13" of the rear'support leg 13 does not have to be rotated, one of the parts 13' or 13" of this rear support leg 13 has only one row of longitudinally spaced apart holes, not shown in the drawing, through which a fixing stud may engage which is pushed through a hole in the other leg portion 13" or 13.

Each support leg 11 and 13 is equipped with a hydraulic cylinder-piston unit 17 which acts between the vehicle 1 and the associated support leg 11 or 13 and serves for swivelling the leg about the horizontal axis and for holding the leg in the desired angular position.

The two forward support legs 11 are adjusted by hand about the vertical axis and may be fixed in a number of angular positions by means of fixing studs or the like relative to the vehicle 1; these fixing elements are not shown in the drawings. On the other hand, the rear support leg 13 has a second hydraulic cylinder-piston unit 18 acting between the vehicle 1 and the support leg 13 and swivelling the same about the vertical axis, whilst simultaneously retaining it relative to the vehicle 1 in the desired angular position.

The two forward support legs 11 are in the fully inward and fixed position located parallel to the longitudinal centre plane of the vehicle 1. In this position of the two forward support legs 11, the wheels 12 are positioned so that they are rotatable about a horizontal axis. These wheels 12 have stub axles 19 which are directed towards each other and over which a link rod 20 is pushed with its ends.

Behind the cab 6, a drive motor, for example an air cooled three-cylinder diesel engine, is mounted on the bottom of the vehicle 1. This drive motor operates through a V-belt a gear pump, not shown, which supplies oil under pressure for the operation of the hydraulic units 17, 18 of the support legs 11 and 13 and for operating the hydraulic crane 7 with the grab 8 and a hydraulic cable winch 21 mounted on the rear deck of the vehicle.

The hydraulic control of the crane 7 with the grab 8, of the cable winch 21 and of the support legs 11 and 13 takes place generally from the cab 6 which also contains the gas lever and the oil pressure gauge for the drive motor, and an operating lever for a clutch for driving a prop shaft.

In this manner, the excavator vehicle 1 according to the invention may be operated by a single operator from the cab 6; this is a great advantage over known excavators which must each be manned by at least two operators.

Underneath the deck 3 there are an oil tank, an oil filter and quick-action stop valves which protect the hydraulic system against overloading.

If the mobile excavator 1 according to the invention is to operate in very wide ditches or channels, a pontoon 2 is mounted on either side of the vehicle 1 near its front edge. For the quick assembly and dismantling of these pontoons 2 without thereby impairing particularly the rigid connection between the pontoons 2 and the vehicle 1, the vehicle 1 has on either side near the base two sloping compartments 22 extending at an angle of about 30 to the vertical downwardly and inwardly. These compartments 22 have on their outer edge a receiving opening and are open at their underside.

Each pontoon 2 has, near the bottom on its side facing the vehicle 1, two sloping holders or supports 23, again forming an angle of about 30 with the vertical and extending downwardly and outwardly. These holders 23 have in the horizontal direction the same distances from each other as the compartments 22 and can easily be pushed into the compartments 22, located on the corresponding side of the vehicle 1. In addition, every pontoon 2 has on top two horizontally projecting eyes or lugs 25 with a hole 24 which can be fitted into recesses or receptacles 26 provided on the outside of the vehicle 1 near the upper edge of the corresponding side.

Each lug 25 is fixed by a fixing stud 27 in the associated receptacle 26; the stud 27 is pushed through holes in the upper wall and the lower wall of the receptacle 26 and through the hole 24 in the lug 25.

The holders 23 and the eyes 25 of each pontoon 2 are located in pairs one above the other near the vertical side edges of the corresponding side of the pontoon. The compartments 22 are provided with guides on which the co-operating holders of the pontoon 2 may be introduced. The eyes 25 consist of wedge-shaped horizontal plates whilst the receptacles 26 have a corresponding wedge-shaped configuration. On the upper wall of each receptacle 26 there is a guide bush 28 for the fixing or holding stud 27 on which rests the head 29 of this stud 27.

For mounting a pontoon 2 on the vehicle 1, the pontoon is first floated parallel to the water and then pushed away from the vehicle with its top edge, so that its side face forms an acute angle with the corresponding side of the vehicle (FIG. 5, left side). The pontoon is then pulled with its lower edge towards the vehicle in such a way that the holders 23 projecting from the bottom edge may enter into the compartments 22 of the vehicle. In consequence of the guides in these compartments, this introduction is very easy, enabling the holdiers 23 to be hooked into the compartments 22 without any difficulties below the water level, i.e., without direct visibility. The pontoon 2 is then pushed down and pulled with its upper edge towards the vehicle 1, causing the lugs 25 to enter the recesses 26 and to be fixed therein easily by means of the fixing studs 27. This results in a perfectly rigid connection between the vehicle l and the pontoon 2. The pontoons 2 connected rigidly with the vehicle 1 in this manner are positioned with their bases at the same level as the bottom of the vehicle 1, as shown in FIGS. 1 and 5, righthand side.

The mobile excavator described above operates as follows.

For moving the vehicle 1 over land, the two forward support legs 11 are fixed in their inwardly pivoted position, extending parallel to the longitudinal centre plane of the vehicle 1. The two wheels 12 are positioned vertically, and the link rod 20 is pushed over the stub axles 19 of these two wheels 12. The rear support leg 13 receives the horizontal axle 15 with the two wheels 16 mounted rotatably thereon.

After starting the engine, the hydraulic system may be operated through the gear pump. Since the gas lever of the engine may control not only the speed of the engine, but also the speed of the gear pump, the output of the gear pump may be controlled.

By operating the hydraulic units 17 of the two forward support legs 11 and of the rear support leg 13, the vehicle 1 with or without pontoons 2 can be lifted off the ground by about 20 cm and may then be moved over the ground by hand, or by a tractor or the like.

The mobility of the vehicle 1 is very high because it can, in fact, be turned about its own axis. To this end, the rear support leg 13 is raised by means of its hydraulic unit 17 in such a way that the rear end of the vehicle is seated on the ground and the wheels 16 are above the ground. Thereafter, the support leg 13 is pivoted about the vertical axis by means of its hydraulic unit 18 in the direction, wherein the rear end of the vehicle 1 has to be displaced. By means of the hydraulic unit 17, the wheels 16 are then pushed down on the ground and the vehicle is raised, whereupon the rear edge of the vehicle 1 is moved by means of the hydraulic unit 18 relative to the wheels 16 resting on the ground. This process is repeated until the vehicle 1 points in the desired direction.

This mobility of the vehicle 1 about its own axis is of particular importance, e.g., when the vehicle 1 is moved along a path alongside a ditch or channel, and must then enter this ditch or channel, since this may frequently necessitate a rotation of the vehicle through about This mobility is also of particular advantage if the vehicle must move out of the water on the slope of the bank.

In order to float the vehicle, the cable of the cable winch 21 is mounted behind the vehicle 1 on a fixed point of the bank. The vehicle 1 travels then with possibly fitted pontoons 2 into the water whilst the cable winch 21 ensures that this manoeuvre is quiet. In order to move the vehicle 1 forward, the crane 7 and the grab 8 may be used by pusing the grab 8 into the ground, whereby the vehicle may then be pushed, pulled or braked. It is even possible to operate without the cable winch 21 for floating the vehicle 1.

As soon as the vehicle is afloat in the water, the link rod 20 between the wheels 12 is removed and the wheels 12 are adjusted to move them into their horizontal position. The axle 15 with the wheels 16 is replaced by the vertical plate member 14. When the wheels 12 are then raised by means of the hydraulic unit 17 of the forward support legs 11 above the surface of the water, and the rear support 13 with the vertical plate member 14 is used as rudder, the vehicle may travel to the working point under its own force.

Where a narrow ditch or a narrow channel is to be excavated the operation takes place without pontoons, and the independently adjustable forward support legs 11 are swivelled out, whilst the horizontally positioned wheels 12, acting as supports are placed on the two banks. The rear support leg 13 is then lowered, causing the vertical plate member 14 to cut into the bottom of the ditch or channel.

Then, the excavation work may be carried out and the mud may be dumped on the banks. The vertical plate member 14, pressed into the bottom, prevents the vehicle 1 from revolving under the reaction force of the slewing crane 7.

Where the mobile excavator according to the invention is to be used in wider ditches or channels, the pontoons 2 are mounted inorder to increase the stability of the vehicle, whilst the forward support legs 11 are adjusted in such a way that the wheels 12, acting as jorixontal support elements, are pushed laterally of the vehicle 1 on to the ground of the ditch or channel.

When the grab 8 has excavated the zone adjacent to and in front of the vehicle 1, it is pushed into the bottom as far as possible from the vehicle, the forward support legs 11 are slightly raised and the hydraulic units 9 of the crane 7 are operated in such a manner that the crane is kinked, causing the grab 8 to pull the vehicle 1 forward. When the vehicle 1 has been pulled forward to such an extent that a new zone can be excavated, the forward support legs 11 are again pressed against the bottom with their horizontally positioned support wheels 12.

In order to move the excavator vehicle 1 according to the invention out of a ditch or channel up the slope of a bank, the wheels 12 are again placed into their vertical position and the plate member 14 of the rear support leg 13 is removed and replaced by the axle 15 with the wheels 16.

Then, the cable of the cable winch 21 is mounted on a fixed point on the bank in front of the vehicle 1, the wheels 12 mounted on the forward support legs 11 are placed on the ground as high up on the slope as possible, the cable is hauled in by the winch 21 and the rear support leg 13 is lowered. Then, the vehicle is pulled by the winch 21 on to the bank. Here again, the grab 8; may be used by depressing it in front of the vehicle into the bank and pulling the vehicle 1 forward by kinking or shortening the crane 7.

Naturally, the invention may be modified in many ways from the embodiment hereinbefore described and is in no way limited to this embodiment.

I claim:

1. An excavator vehicle with a crane mounted near one end rotatably about a vertical axis, wherein the vehicle has proximate said end two support legs with adjustable length, adapted to be pivoted at their end connected to the vehicle about a horizontal and a vertical axis and to be fixed in both directions at different angular positions relative to the vehicle, said legs each having at their free ends support means adapted to be rotated about a horizontal axis, said vehicle having at its other end, a third support leg pivotable at its end mounted on the vehicle about a vertical and a horizontal axis and adapted to be fixed in both directions in different angular positions relative to the vehicle, and said third support leg having at its free end vertically extending support means.

2. An excavator vehicle according to claim 1, wherein the two first support legs are mounted on the front side of the vehicle, near the two edges thereof.

3. An excavator vehicle according to claim 1, wherein the end of the third support leg connected to the vehicle, is located in the longitudinal centre plane of the vehicle.

5. An excavator vehicle according to claim 4,-

wherein each telescopic support leg includes one part having longitudinally spaced apart holes, and a fixing stud adapted to be pushed through one of said holes and a hole in the adjacent part of the support leg providing for longitudinal adjustment of each leg.

6. An excavator vehicle according to claim 1, wherein the support means on the free ends of said two first support legs each comprise a wheel rotatable about a horizontal axis and adapted to be turned into the horizontal for use as support, in which horizontal position the wheel is adapted to be secured against rotation.

7. An excavator vehicle according to claim 6, wherein each telescopic support leg consists of two parts, while the outer part of each of the two first support legs carrying a wheel at its free end is adapted to be rotated about its longitudinal axis relative to the adjacent support leg part, whilst one of the parts of each of said first support legs has two rows of longitudinally spaced apart holes, wherein the holes of one row are located in a plane of said part of the support leg which is perpendicular to the plane containing the other row of holes.

8. An. excavator vehicle according to claim 1, wherein a drive, such as a hydraulic cylinder-piston unit is provided for swivelling each support leg about its horizontal axis, and for fixing the support leg in the desired position.

9. An excavator vehicle according to claim 8, wherein a drive, such as a hydraulic cylinder-piston unit acting between the vehicle and the third support leg is provided for swivelling the third support leg about its vertical axis and for fixing the support leg in the desired angular position relative to the vehicle.

10. An excavator vehicle according to claim 8, wherein the two first support legs are adapted to be swivelled by hand about the vertical axis and may be fixed by a fixing stud in a number of angular positions relative to the vehicle.

11. An excavator vehicle according to claim 1, wherein the two first support legs have in their position parallel to the longitudinal centre plane of the vehicle and with the wheels rotatable about the horizontal axis, each a stub axle pointing towards the other support leg and are connected by a link rod fitted over these two stub axles.

12. An excavator vehicle according to claim 11, wherein the support means on the free end of said third support leg includes a horizontal axle, and two wheels rotatable about said axle.

13. An excavator vehicle according to claim 1, wherein the vehicle is adapted to be driven by an engine operable from the cab, which engine drives simultaneously an oil pump, and the same is connected with hydraulic cylinder-piston units for swivelling said support legs, with the hydraulic drive of the crane, with a grab mounted on the crane, and with a hydraulic winch carried by the vehicle at the end remote from the crane, wherein the control valves for the hydraulic installation are also operable from the cab.

14. An excavator vehicle according to claim 1, said support means on the free ends of said two first support legs each comprising a substantially horizontally extending support member.

15. An excavator vehicle according to claim 1, said support means on the free end of said third support leg comprising a vertical plate member. 

1. An excavator vehicle with a crane mounted near one end rotatably about a vertical axis, wherein the vehicle has proximate said end two support legs with adjustable length, adapted to be pivoted at their end connected to the vehiCle about a horizontal and a vertical axis and to be fixed in both directions at different angular positions relative to the vehicle, said legs each having at their free ends support means adapted to be rotated about a horizontal axis, said vehicle having at its other end, a third support leg pivotable at its end mounted on the vehicle about a vertical and a horizontal axis and adapted to be fixed in both directions in different angular positions relative to the vehicle, and said third support leg having at its free end vertically extending support means.
 2. An excavator vehicle according to claim 1, wherein the two first support legs are mounted on the front side of the vehicle, near the two edges thereof.
 3. An excavator vehicle according to claim 1, wherein the end of the third support leg connected to the vehicle, is located in the longitudinal centre plane of the vehicle.
 4. An excavator vehicle according to claim 1, wherein all support legs are telescopic legs.
 5. An excavator vehicle according to claim 4, wherein each telescopic support leg includes one part having longitudinally spaced apart holes, and a fixing stud adapted to be pushed through one of said holes and a hole in the adjacent part of the support leg providing for longitudinal adjustment of each leg.
 6. An excavator vehicle according to claim 1, wherein the support means on the free ends of said two first support legs each comprise a wheel rotatable about a horizontal axis and adapted to be turned into the horizontal for use as support, in which horizontal position the wheel is adapted to be secured against rotation.
 7. An excavator vehicle according to claim 6, wherein each telescopic support leg consists of two parts, while the outer part of each of the two first support legs carrying a wheel at its free end is adapted to be rotated about its longitudinal axis relative to the adjacent support leg part, whilst one of the parts of each of said first support legs has two rows of longitudinally spaced apart holes, wherein the holes of one row are located in a plane of said part of the support leg which is perpendicular to the plane containing the other row of holes.
 8. An excavator vehicle according to claim 1, wherein a drive, such as a hydraulic cylinder-piston unit is provided for swivelling each support leg about its horizontal axis, and for fixing the support leg in the desired position.
 9. An excavator vehicle according to claim 8, wherein a drive, such as a hydraulic cylinder-piston unit acting between the vehicle and the third support leg is provided for swivelling the third support leg about its vertical axis and for fixing the support leg in the desired angular position relative to the vehicle.
 10. An excavator vehicle according to claim 8, wherein the two first support legs are adapted to be swivelled by hand about the vertical axis and may be fixed by a fixing stud in a number of angular positions relative to the vehicle.
 11. An excavator vehicle according to claim 1, wherein the two first support legs have in their position parallel to the longitudinal centre plane of the vehicle and with the wheels rotatable about the horizontal axis, each a stub axle pointing towards the other support leg and are connected by a link rod fitted over these two stub axles.
 12. An excavator vehicle according to claim 11, wherein the support means on the free end of said third support leg includes a horizontal axle, and two wheels rotatable about said axle.
 13. An excavator vehicle according to claim 1, wherein the vehicle is adapted to be driven by an engine operable from the cab, which engine drives simultaneously an oil pump, and the same is connected with hydraulic cylinder-piston units for swivelling said support legs, with the hydraulic drive of the crane, with a grab mounted on the crane, and with a hydraulic winch carried by the vehicle at the end remote from the crane, wherein the control valves for the hydraulic installation are also operable from the cab.
 14. An exCavator vehicle according to claim 1, said support means on the free ends of said two first support legs each comprising a substantially horizontally extending support member.
 15. An excavator vehicle according to claim 1, said support means on the free end of said third support leg comprising a vertical plate member. 